Grinding of flat clothing is described in "Handbuch der textilen Fertigung, Die Kurzstapelspinnerei" (Handbook of Textile Manufacturing, Short Staple Spinning) Volume 2: Putzerei und Karderie (Opening and Cleaning) (The Textile Institute, Author: W. Klein), p.58/59. The means applied in this process are well known since a long time--compare e.g. GB 22533 issued 1895, DE 61636 issued 1891 and DE 606 832 issued 1933. A further proposal suggesting that the revolving flat arrangement can be taken off the machine as a "module" for maintenance purposes is shown in DE 2741089 by Trutzschler. A more recent grinding apparatus was described also in JP 57-112415 (published Jul. 13, 1982).
In EP-C-322637 a grinding apparatus has been shown which constantly is in operation, or operable respectively. This apparatus can be applied to grinding the clothing of a flat, and a corresponding embodiment has been shown in FIG. 3 of the EP-C-322637 which in the following will be discussed with reference to FIG. 2 of the present application; a more detailed discussion being dispensed with here.